Android (lack of) support for DHCPv6

Wed Jun 10 14:58:23 UTC 2015

On Wed, Jun 10, 2015 at 10:06 PM, Ray Soucy <rps at maine.edu> wrote:

> Actually we do support DHCPv6-PD, but Android doesn't even support DHCPv6
> let alone PD, so that's the discussion here, isn't it?
>

It is possible to implement DHCPv6 without implementing stateful address
assignment.

If there were consensus that delegating a prefix of sufficient size via
DHCPv6 PD of a sufficient size is an acceptable substitute for stateful
IPv6 addressing in the environments that currently insist on stateful
DHCPv6 addressing, then it would make sense to implement it. In that
scenario, Android would still not implement DHCPv6 NA, but it would
implement DHCPv6 PD.

What needs to be gauged about that course of action is how much consensus
would be achieved, whether network operators would actually use it (IPv6
has a long and distinguished history of people claiming "I can't support
IPv6 until I get feature X", feature X appearing, and people changing their
claim to "I can't support IPv6 until I get feature Y"), and how much of
this discussion would be put to bed.

That course of action would seem most feasible if it were accompanied by an
IETF document that explained the deployment model and clarified what
"sufficient size" is.

> Universities see a constant stream of DMCA violation notices that need to
> be dealt with and not being able to associate a specific IPv6 address to a
> specific user is a big enough liability that the only option is to not use
> IPv6.
>

It's not the *only* option. There are large networks - O(100k) IPv6 nodes -
that do ND monitoring for accountability, and it does work for them. Many
devices support this via syslog, even. As you can imagine, my Android
device gets IPv6 at work, even though it doesn't support DHCPv6. Other
universities, too. It's obviously  not your chosen or preferred mechanism,
but it does work.